I can't add more simulator OS version in XCode 12, for example iOS 13, the list is empty:
how can I add more simulatore with different ios version?
I solved this by going to the apple developer download page https://developer.apple.com/download/ and downloading the XCode 12.2 beta.
I threw my other version of XCode in the trash. I was able to see all the normal iOS simulator runtimes that are missing from your screenshot.
Update: It appears that the issue is resolved in Xcode 12.2 Beta 2.
I had exact same problem, apple returns empty list of simulators. Here is what I did:
First install xcode-install gem (follow readme):
Then check what iOS simulators are available:
Finally install desired simulator i.e: